Hand-writing pen is an important information inputting device. With the continuous popularization of various mobile terminals, such as cell phones, having a touch screen function, the hand-writing pen also becomes more and more popular.
At the same time, when taking angle or length measurements, people need an additional measurement tool to take measurements. However, modern social people usually do not carry any measurement tool with themselves except some specialists.
In the related art, the measurement of length and angle is realized by way of adding calibrations or a dial on the shell of a mobile terminal, which will affect the appearance of the mobile terminal and make it inconvenient to measure the angle of graphics on a page. Regarding the problems in the related art, no effective solution has been presented currently.